This invention relates to chassis for holding telecommunications cards such as repeater circuits. More specifically, the present invention relates to chassis and cards with flame spread containment features.
A chassis for holding telecommunication circuit cards must support a sufficient density of cards to be effective, yet it must also effectively dissipate heat developed during operation while containing the spread of flames should a fire be imposed within the chassis. The cards installed in the chassis perform electrical operations, such as signal transception and amplification that generate a significant amount of heat. Typically, a chassis is installed in a rack that contains several other chassis stacked above and below. The heat and flames that may develop within a chassis in the rack have the potential to harm circuit cards housed in the chassis above and below the chassis where the heat and/or flames emanate from.
The chassis must also provide external protection for the circuit cards it houses. Thus, the chassis cannot freely expose the circuit cards to areas outside the chassis when attempting to dissipate heat and flames. Additionally, the chassis must provide a structural interconnection that maintains electrical continuity between the circuit cards and external transmission mediums such as copper wires or fiber optic cables while facilitating insertion and removal of the cards. A sufficient structure must be used to facilitate this circuit card modularity, which further limits the chassis"" ability to provide outlets for heat and flames.
Thus several factors must be accounted for in the chassis and card design. Chassis designs with large interior spaces for directing heat and flames away from circuit cards may be undesirable because the chassis may become too large to accommodate a high density of circuits. Chassis designs with open exteriors for directing heat and flames away from the circuit cards may be undesirable because the circuit cards may not be sufficiently protected from externalities such as falling objects or heat and flames spreading from a chassis positioned above or below in the rack.
Thus, there is a need for a chassis and card design whereby the chassis may contain a high density of readily removable circuit cards while providing effective heat dissipation and flame containment.
The present invention provides a chassis and card design that may accommodate a high density of readily removable circuits while providing heat dissipation and flame containment features. Ventilation and containment structure are employed to direct heat away from internal circuitry while preventing flames from spreading within the chassis. Additionally, chassis designs of the present invention may provide exterior features that establish protection from externalities and prevent the harmful spread of heat and flames to chassis or other equipment stacked above or below.
The present invention may be viewed as a chassis for housing telecommunications cards. The chassis includes an inner housing with vertical sidewalls, a top surface, and a bottom surface, wherein the top surface and the bottom surface have a plurality of openings. A middle floor is disposed within the inner housing dividing the inner housing into a top chamber and a bottom chamber and includes a bottom plate and a top plate. The top plate overlays the bottom plate with a separation between at least portions of the top plate and the bottom plate, and the bottom plate has openings that at least partially align with openings provided in the top plate. A first cover overlays the top surface, and a bottom cover underlays the bottom surface.
The present invention may also be viewed as another chassis for housing telecommunications cards. The chassis includes an inner housing with vertical sidewalls, a top surface, a bottom surface, and a plurality of spaced inner side walls forming a plurality of compartments within the inner housing, wherein the top surface and the bottom surface have a plurality of spaced slots. A middle floor is disposed within the inner housing dividing each of the plurality of chambers into a top chamber and a bottom chamber, and it includes a bottom plate and a top plate with the top plate overlaying the bottom plate with a separation between at least portions of the top plate and the bottom plate. The bottom plate has slots that partially align with slots provided in the top plate. A first mesh cover overlays at least a portion of the top surface of the inner housing, and a second mesh cover overlays the first mesh cover and the top surface with a separation existing between the second mesh cover and the first mesh cover. A bottom mesh cover underlays the bottom surface of the inner housing.
The present invention may be viewed as another chassis for housing telecommunications cards. The chassis includes an inner housing with vertical sidewalls, a top surface, and a bottom surface, with the top surface and the bottom surface having a plurality of openings. A first mesh cover overlays at least a portion of the top surface of the inner housing, and a second mesh cover overlays the first mesh cover and the top surface with a separation existing between the second mesh cover and the first mesh cover.
The present invention may also be viewed as another chassis for housing telecommunications cards. The chassis includes an inner housing with vertical sidewalls, a first horizontal surface, and a second horizontal surface separated from the first horizontal surface by the vertical sidewalls, with the first horizontal surface and the second horizontal surface having a plurality of openings. A third horizontal surface is disposed within the inner housing between the first and second horizontal surfaces that divides the inner housing into a top chamber and a bottom chamber. The third horizontal surface includes a first horizontal plate and a second horizontal plate, wherein the first horizontal plate overlays the second horizontal plate with a separation between at least portions of the first horizontal plate and the second horizontal plate, and wherein the first horizontal surface and first horizontal plate define first and second horizontal surfaces of the top chamber and one of the horizontal surfaces of the top chamber has grooves and the other horizontal surface of the top chamber has projections for receiving a fin and guide of a telecommunications card. The second horizontal surface and second horizontal plate define first and second horizontal surfaces of the bottom chamber and one of the horizontal surfaces of the bottom chamber has grooves and the other horizontal surface of the bottom chamber has projections for receiving a fin and guide of a telecommunications card. A first cover is disposed over at least a portion of an outer portion of the first horizontal surface, and a second cover is disposed over at least a portion of an outer portion of the second horizontal surface.
The present invention may be viewed as a circuit card for installation in a chassis. The card includes a printed circuit board populated with electrical circuitry having a first electrical connector for connection to a second electrical connector in the chassis. The first electrical connector is positioned on a first edge of the printed circuit board, and the printed circuit board establishes a first spatial plane. A faceplate is positioned at a second edge of the printed circuit board opposite to the first edge. A guide is mounted to the printed circuit board along a third edge that is substantially perpendicular to the first and second edges, and the guide establishes a second spatial plane perpendicular to the first spatial plane. The guide has at least one opening.
The present invention may also be viewed as another circuit card for installation in a chassis. The circuit card includes a printed circuit board populated with electrical circuitry having a first electrical connector for connection to a second electrical connector in the chassis. The first electrical connector is positioned on a first edge of the printed circuit board, and the printed circuit board establishes a first spatial plane. A faceplate for abutting a chassis is also included and is positioned at a second edge of the printed circuit board opposite to the first edge. The faceplate has a finger extending from the faceplate and away from the printed circuit board. A guide is mounted to the printed circuit board along a third edge.